Distractor Words Research Articles

Electrophysiology of cross-language interference and facilitation in picture naming

Disagreement exists about how bilingual speakers select words, in particular, whether words in another language compete, or competition is restricted to a target language, or no competition occurs. Evidence that competition occurs but is restricted to a target language comes from response time (RT) effects obtained when speakers name pictures in one language while trying to ignore distractor words in another language. Compared to unrelated distractor words, RT is longer when the picture name and distractor are semantically related, but RT is shorter when the distractor is the translation of the name of the picture in the other language. These effects suggest that distractor words from another language do not compete themselves but activate their counterparts in the target language, thereby yielding the semantic interference and translation facilitation effects. Here, we report an event-related brain potential (ERP) study testing the prediction that priming underlies both of these effects. The RTs showed semantic interference and translation facilitation effects. Moreover, the picture-word stimuli yielded an N400 response, whose amplitude was smaller on semantic and translation trials than on unrelated trials, providing evidence that interference and facilitation priming underlie the RT effects. We present the results of computer simulations showing the utility of a within-language competition account of our findings.

Effects of concurrent task demands on language planning in fluent children and adults.

The aim of the present study was to investigate how children and adults allocate cognitive resources to performing segmental encoding and monitoring in a dual task paradigm and the response patterns of the primary and secondary tasks in the dual task. Participants were 20 children divided equally into two age groups-7 to 11 years, 12 to 15 years, and 10 adults. The primary task required participants to monitor phonemic segments in a picture - written word interference paradigm while silently naming the pictures. The picture and distractor word were the same (replica), related (phoneme onset overlap), or unrelated. The secondary task required participants to make pitch judgments on tones presented at short (330 ms) or long (1130 ms) stimulus onset asynchrony (SOA) from picture onset. Developmental differences were observed in both response times and percent errors in the primary and secondary tasks. Slower responses to the primary task were evident at the long SOA, related condition. Slower response times to the tone decision task were evident at the short than the long SOA. The findings support the capacity sharing account of dual task performance and suggest that dual task costs during language planning are higher in children than adults.

History of childhood maltreatment augments dorsolateral prefrontal processing of emotional valence in PTSD

Posttraumatic stress disorder (PTSD) is characterized by conflicting findings of both increased and decreased amygdala and prefrontal reactivity to threat or trauma stimuli. Childhood maltreatment (CM), a potent risk factor for PTSD, exerts long-lasting influences on threat processing and prefrontal-amygdala function. This suggests that CM history may influence PTSD neural phenotypes related to threat processing. Here, we adapt a well-characterized emotional conflict paradigm to investigate CM effects on both emotional conflict and emotional valence processing within PTSD stratified by task relevance. Forty-two individuals with PTSD (22 reporting extensive CM history (PTSD-CM)) and 20 trauma-exposed healthy controls (TEHCs) underwent functional magnetic resonance imaging while identifying affect of emotional faces (fear and happy) overlaid with a goal-irrelevant emotional distractor word (“FEAR” or “HAPPY”). We examined effects of CM on conflict, conflict adaptation, valence-related activation (fear vs. happy) for goal-relevant (face) and goal-irrelevant stimuli (word), and valence effects in interaction with goal-relevancy (face vs. word). Though no activation differences between groups were observed for conflict contrasts nor for valence effects in the amygdala, CM status interacted with valence processing differences as a function of goal relevance in the left dorsolateral prefrontal cortex (dlPFC). Here, PTSD-CM displayed greater activation relative to PTSD to negative valence when stimuli were goal-irrelevant. CM history also moderated relationships between activation abnormalities and PTSD re-experiencing symptoms. These findings provide initial evidence that CM history augments dorsolateral prefrontal bias to implicitly processed stimulus valence in PTSD.

The effects of thematic relations on picture naming abilities across the lifespan

ABSTRACTA picture–word interference paradigm tracked patterns of activation during picture naming in 87 individuals (age range 17–80 years old). Distractor words were presented at stimulus onset asynchronies (SOAs) of −200, −100, and 0 ms bearing a has a-, location, or no relationship to the picture. Analyses of group naming reaction times revealed significant facilitation effects for both semantic relation types for all age groups. Analyses of temporal patterns of activation revealed significant effects primarily at SOAs of −200 and −100 ms. These findings provide evidence that both thematic relations are particularly salient in how semantic knowledge is organized, and that the patterns of effects from these semantic relations remain the same as one ages.

Competing influences of emotion and phonology during picture-word interference

ABSTRACTSpeaking is susceptible to distraction, illustrated by slowed picture naming in the presence of taboo distractor words. However, other distractors such as phonologically related words speed picture naming. Two experiments explored the simultaneous influences of these competing factors. Participants named target pictures superimposed with taboo, negative, positive, or neutral distractor words, and filler pictures were presented after every target to investigate emotional carryover effects. Distractors were phonologically related or unrelated to the target (Experiment 1) or filler (Experiment 2). Results showed that taboo, and to a lesser extent negative, distractors slowed picture naming relative to neutral and positive distractors, and slowing from taboo distractors persisted into the filler trial. In contrast, phonological overlap between targets and distractors sped target but not filler picture naming, especially when distractors were taboo. These findings suggest that strong emotional words engage attention to influence phonological encoding during speech production, and interfering effects from taboo words are particularly long lasting. Results are interpreted within existing language production theories, using mechanisms that are sensitive to words’ emotional properties and that regulate distractor interference during speech production.

Early and Late Electrophysiological Effects of Distractor Frequency in Picture Naming: Reconciling Input and Output Accounts.

The "distractor-frequency effect" refers to the finding that high-frequency (HF) distractor words slow picture naming less than low-frequency distractors in the picture-word interference paradigm. Rival input and output accounts of this effect have been proposed. The former attributes the effect to attentional selection mechanisms operating during distractor recognition, whereas the latter attributes it to monitoring/decision mechanisms operating on distractor and target responses in an articulatory buffer. Using high-density (128-channel) EEG, we tested hypotheses from these rival accounts. In addition to conducting stimulus- and response-locked whole-brain corrected analyses, we investigated the correct-related negativity, an ERP observed on correct trials at fronto-central electrodes proposed to reflect the involvement of domain general monitoring. The whole-brain ERP analysis revealed a significant effect of distractor frequency at inferior right frontal and temporal sites between 100 and 300-msec post-stimulus onset, during which lexical access is thought to occur. Response-locked, region of interest (ROI) analyses of fronto-central electrodes revealed a correct-related negativity starting 121 msec before and peaking 125 msec after vocal onset on the grand averages. Slope analysis of this component revealed a significant difference between HF and low-frequency distractor words, with the former associated with a steeper slope on the time window spanning from 100 msec before to 100 msec after vocal onset. The finding of ERP effects in time windows and components corresponding to both lexical processing and monitoring suggests the distractor frequency effect is most likely associated with more than one physiological mechanism.

Pre-target oscillatory brain activity and the attentional blink.

Reporting the second of two targets within a stream of distracting words during rapid serial visual presentation (RSVP) is impaired when the targets are separated by a single distractor word, a deficit in temporal attention that has been referred to as the attentional blink (AB). Recent conceptual and empirical work has pointed to pre-target brain states as potential mediators of the AB effect. The current study examined differences in pre-target electrophysiology between correctly and incorrectly reported trials, considering amplitude and phase measures of alpha oscillations as well as the steady-state visual evoked potential (ssVEP) evoked by the RSVP stream. For incorrectly reported trials, relatively lower alpha-band power and greater ssVEP inter-trial phase locking were observed during extended time periods preceding presentation of the first target. These results suggest that facilitated processing of the pre-target distracter stream indexed by reduced alpha and heightened phase locking characterizes a dynamic brain state that predicts lower accuracy in terms of reporting the second target under strict temporal constraints. Findings align with hypotheses in which the AB effect is attributed to neurocognitive factors such as fluctuations in pre-target attention or to cognitive strategies applied at the trial level.

Semantic interference in picture naming during dual-task performance does not vary with reading ability.

Previous dual-task studies examining the locus of semantic interference of distractor words in picture naming have obtained diverging results. In these studies, participants manually responded to tones and named pictures while ignoring distractor words (picture-word interference, PWI) with varying stimulus onset asynchrony (SOA) between tone and PWI stimulus. Whereas some studies observed no semantic interference at short SOAs, other studies observed effects of similar magnitude at short and long SOAs. The absence of semantic interference in some studies may perhaps be due to better reading skill of participants in these than in the other studies. According to such a reading-ability account, participants' reading skill should be predictive of the magnitude of their interference effect at short SOAs. To test this account, we conducted a dual-task study with tone discrimination and PWI tasks and measured participants' reading ability. The semantic interference effect was of similar magnitude at both short and long SOAs. Participants' reading ability was predictive of their naming speed but not of their semantic interference effect, contrary to the reading ability account. We conclude that the magnitude of semantic interference in picture naming during dual-task performance does not depend on reading skill.

The Effect of Target Repetition on Semantic Priming in a Three-Target RSVP Task

This study used a rapid serial visual presentation task to examine the impact of target relatedness on report accuracy. In this task participants were shown a series of briefly presented words and were required to identify the three colored target words from the stream of distractor words. In two experiments participants either recalled the three targets words from memory at the end of each trial or recognized the targets from a list of all possible targets. The first target shown on each trial was unrelated to the second or third target. The second and third targets within each stream were semantically related (e.g., dog and cat) on half the trials and unrelated on the other half the trials (e.g., table and cat). The effect of the second and third targets sharing a relationship was examined for Target 3 accuracy. Target 3 accuracy was greater if it was preceded by a related Target 2, compared to when Targets 2 and 3 were unrelated. This shows a semantic priming effect (facilitation effect) for Target 3 accuracy, when the both Target 2 and 3 were identified. In contrast, when Target 2 was missed or incorrectly reported there was no difference in accuracy for related or unrelated target contexts (no priming or facilitation effect for Target 3). These semantic priming effects were evident in the recall and recognition tasks in Experiment 1 and 2. This study shows that a target presented during a rapid serial visual presentation task must be consciously processed to facilitate the report of a subsequently presented target word.

Listening to Puns Elicits the Co-Activation of Alternative Homophone Meanings during Language Production.

Recent evidence suggests that lexical-semantic activation spread during language production can be dynamically shaped by contextual factors. In this study we investigated whether semantic processing modes can also affect lexical-semantic activation during word production. Specifically, we tested whether the processing of linguistic ambiguities, presented in the form of puns, has an influence on the co-activation of unrelated meanings of homophones in a subsequent language production task. In a picture-word interference paradigm with word distractors that were semantically related or unrelated to the non-depicted meanings of homophones we found facilitation induced by related words only when participants listened to puns before object naming, but not when they heard jokes with unambiguous linguistic stimuli. This finding suggests that a semantic processing mode of ambiguity perception can induce the co-activation of alternative homophone meanings during speech planning.

Serial order in word form retrieval: New insights from the auditory picture-word interference task.

One important theoretical question about word production concerns whether the phonemes of a word are retrieved in parallel or in sequential order. To address this question, Meyer and Schriefers (Journal of Experimental Psychology: Learning, Memory, and Cognition 17:1146-1160, 1991) used an auditory picture-word interference task and manipulated the position of the phonemes shared between a distractor word and a target picture. They found that begin-related distractors (e.g., boat-bone) facilitated naming times when they were presented within 150ms before or after the picture, whereas end-related distractors (e.g., cone-bone) were effective only if presented within 150ms after the picture. This suggested that the word's end phonemes were activated later than the beginning ones. However, it remained unclear whether these effects genuinely reflected facilitation at the level of phonological retrieval. In this study, we examined later distractor presentation onsets, so that the distractors had little opportunity to influence earlier, lexical selection processes. At the latest onset tested, end-related-but not begin-related-distractors significantly facilitated naming. We concluded that late-presented distractors do indeed influence phonological encoding, and that their asymmetric effects support a sequential model of phoneme retrieval.

When Distraction Holds Relevance: A Prospective Memory Benefit for Older Adults.

Evidence is accumulating to show that age-related increases in susceptibility to distracting information can benefit older more than young adults in several cognitive tasks. Here we focus on prospective memory (i.e., remembering to carry out future intentions) and examine the effect of presenting distracting information that is intention-related as a function of age. Young and older adults performed an ongoing 1-back working memory task to a rapid stream of pictures superimposed with to-be-ignored letter strings. Participants were additionally instructed to respond to target pictures (namely, animals) and, for half of the participants, some strings prior to the targets were intention-related words (i.e., animals). Results showed that presenting intention-related distracting information during the ongoing task was particularly advantageous for target detection in older compared to young adults. Moreover, a prospective memory benefit was observed even for older adults who showed no explicit memory for the target distracter words. We speculate that intention-related distracter information enhanced the accessibility of the prospective memory task and suggest that when distracting information holds relevance to intentions it can serve a compensatory role in prospective remembering in older adults.

Greater priming for previously distracting information in young than older adults when suppression is ruled out

The use of previously distracting information on memory tests with indirect instructions is usually age-equivalent, while young adults typically show greater explicit memory for such information. This could reflect qualitatively distinct initial processing (encoding) of distracting information by younger and older adults, but could also be caused by greater suppression of such information by younger adults on tasks with indirect instructions. In Experiment 1, young and older adults read stories containing distracting words, which they ignored, before studying a list of words containing previously distracting items for a free recall task. Half the participants were informed of the presence of previously distracting items in the study list prior to recall (direct instruction), and half were not (indirect instruction). Recall of previously distracting words was age-equivalent in the indirect condition, but young adults recalled more distracting words in the direct condition. In Experiment 2, participants performed the continuous identification with recognition task, which captures a measure of perceptual priming and recognition on each trial, and is immune to suppression. Priming and recognition of previously distracting words was greater in younger than older adults, suggesting that the young engage in more successful suppression of previously distracting information on tasks in which its relevance is not overtly signaled.

Conflict resolved: On the role of spatial attention in reading and color naming tasks.

The debate about whether or not visual word recognition requires spatial attention has been marked by a conflict: the results from different tasks yield different conclusions. Experiments in which the primary task is reading based show no evidence that unattended words are processed, whereas when the primary task is color identification, supposedly unattended words do affect processing. However, the color stimuli used to date does not appear to demand as much spatial attention as explicit word reading tasks. We first identify a color stimulus that requires as much spatial attention to identify as does a word. We then demonstrate that when spatial attention is appropriately captured, distractor words in unattended locations do not affect color identification. We conclude that there is no word identification without spatial attention.

Language co-activation and lexical selection in bimodal bilinguals: Evidence from picture-word interference.

We used picture-word interference (PWI) to discover a) whether cross-language activation at the lexical level can yield phonological priming effects when languages do not share phonological representations, and b) whether semantic interference effects occur without articulatory competition. Bimodal bilinguals fluent in American Sign Language (ASL) and English named pictures in ASL while listening to distractor words that were 1) translation equivalents, 2) phonologically related to the target sign through translation, 3) semantically related, or 4) unrelated. Monolingual speakers named pictures in English. Production of ASL signs was facilitated by words that were phonologically related through translation and by translation equivalents, indicating that cross-language activation spreads from lexical to phonological levels for production. Semantic interference effects were not observed for bimodal bilinguals, providing some support for a post-lexical locus of semantic interference, but which we suggest may instead reflect time course differences in spoken and signed production in the PWI task.

Searching for the right word: Hybrid visual and memory search for words.

In "hybrid search" (Wolfe Psychological Science, 23(7), 698-703, 2012), observers search through visual space for any of multiple targets held in memory. With photorealistic objects as the stimuli, response times (RTs) increase linearly with the visual set size and logarithmically with the memory set size, even when over 100 items are committed to memory. It is well-established that pictures of objects are particularly easy to memorize (Brady, Konkle, Alvarez, & Oliva Proceedings of the National Academy of Sciences, 105, 14325-14329, 2008). Would hybrid-search performance be similar if the targets were words or phrases, in which word order can be important, so that the processes of memorization might be different? In Experiment 1, observers memorized 2, 4, 8, or 16 words in four different blocks. After passing a memory test, confirming their memorization of the list, the observers searched for these words in visual displays containing two to 16 words. Replicating Wolfe (Psychological Science, 23(7), 698-703, 2012), the RTs increased linearly with the visual set size and logarithmically with the length of the word list. The word lists of Experiment 1 were random. In Experiment 2, words were drawn from phrases that observers reported knowing by heart (e.g., "London Bridge is falling down"). Observers were asked to provide four phrases, ranging in length from two words to no less than 20 words (range 21-86). All words longer than two characters from the phrase, constituted the target list. Distractor words were matched for length and frequency. Even with these strongly ordered lists, the results again replicated the curvilinear function of memory set size seen in hybrid search. One might expect to find serial position effects, perhaps reducing the RTs for the first (primacy) and/or the last (recency) members of a list (Atkinson & Shiffrin, 1968; Murdock Journal of Experimental Psychology, 64, 482-488, 1962). Surprisingly, we showed no reliable effects of word order. Thus, in "London Bridge is falling down," "London" and "down" were found no faster than "falling."

Task choice and semantic interference in picture naming

Evidence from dual-task performance indicates that speakers prefer not to select simultaneous responses in picture naming and another unrelated task, suggesting a response selection bottleneck in naming. In particular, when participants respond to tones with a manual response and name pictures with superimposed semantically related or unrelated distractor words, semantic interference in naming tends to be constant across stimulus onset asynchronies (SOAs) between the tone stimulus and the picture–word stimulus. In the present study, we examine whether semantic interference in picture naming depends on SOA in case of a task choice (naming the picture vs reading the word of a picture–word stimulus) based on tones. This situation requires concurrent processing of the tone stimulus and the picture–word stimulus, but not a manual response to the tones. On each trial, participants either named a picture or read aloud a word depending on the pitch of a tone, which was presented simultaneously with picture–word onset or 350ms or 1000ms before picture–word onset. Semantic interference was present with tone pre-exposure, but absent when tone and picture-word stimulus were presented simultaneously. Against the background of the available studies, these results support an account according to which speakers tend to avoid concurrent response selection, but can engage in other types of concurrent processing, such as task choices.

Typicality effects in picture-word interference paradigm: An evaluation of the response exclusion hypothesis.

The response exclusion hypothesis suggests that the polarity of semantic effects in the picture-word interference paradigm is determined by the response-relevant criteria. Semantic interference effects would be observed when semantically related distractor words satisfy the response-relevant criteria; otherwise, semantic facilitation effects should be found. The purpose of this study was to further evaluate the response exclusion hypothesis by exploring the typicality effects in pictures naming. In two experiments, pictures of objects were named either in the context of verb distractor words with different typicality of passive functions or in the context of adjective distractor words with different typicality of characteristics. Facilitation effects were observed in context of typical verbs and adjectives, while interference effects were observed in the context of atypical verbs and adjectives. Given that neither typical nor atypical distractor words satisfy the response-relevant criteria to produce noun, these findings are problematic for the response exclusion hypothesis. Role of syntagmatic relationships in lexical retrieval was invoked to explain present findings.

On the relationship between negative affective priming and prefrontal cognitive control mechanisms

Although several studies have examined inhibition of affective stimuli, valence-dependent cognitive control effects remain poorly understood. Behavioural and functional imaging (functional magnetic resonance imaging) data were collected from 17 healthy participants to examine neural correlates of the Negative Affective Priming (NAP) task. We created relative ratio scores considering the reaction times of prime trials in order to assess the amount of interference after the presentation of negative and positive distracter words. Behavioural results showed an attenuated NAP effect for negative distracters compared to neutral stimuli. Furthermore, priming negative distracters generated more interference by reacting to the probe target than positive distracters. Neuroimaging data revealed a stronger prefrontal activation during negative NAP trials compared to positive NAP and neutral control trials, which was reflected in a heightened activation of superior and middle frontal gyrus as well as parietal cortex. The findings show the impact of negative distracters on prefrontal response, contributing to the understanding of NAP effects in healthy subjects.

Neural correlates of an early attentional capture by positive distractor words.

Exogenous or automatic attention to emotional distractors has been observed for emotional scenes and faces. In the language domain, however, automatic attention capture by emotional words has been scarcely investigated. In the current event-related potentials study we explored distractor effects elicited by positive, negative and neutral words in a concurrent but distinct target distractor paradigm. Specifically, participants performed a digit categorization task in which task-irrelevant words were flanked by numbers. The results of both temporo-spatial principal component and source location analyses revealed the existence of early distractor effects that were specifically triggered by positive words. At the scalp level, task-irrelevant positive compared to neutral and negative words elicited larger amplitudes in an anterior negative component that peaked around 120 ms. Also, at the voxel level, positive distractor words increased activity in orbitofrontal regions compared to negative words. These results suggest that positive distractor words quickly and automatically capture attentional resources diverting them from the task where attention was voluntarily directed.